Bicycles have proved to be very efficient vehicles for converting human energy into mechanical energy in order to produce self-propelled motion. Despite their usefulness, many bicycles suffer from one problem that can dampen the enthusiasm of the most ardent cyclist. The problem is that bicycles are not very good shock absorbers. Consequently, many of the bumps and jolts that a bicycle is exposed to are transferred with little reduction in frequency or amplitude to the cyclist. These shocks must then be absorbed by the cyclist's body, which, over time, may not be able to withstand their effects. Shock exposure is of special concern to persons who enjoy either "mountain" or "off-road" bicycling and to persons who enjoy distance bicycling. Mountain and off-road bicyclists are exposed to a significant amount of shock because the surfaces on which they ride are quite uneven and, consequently, many of the terrain bumps are simply passed through the bicycle to the cyclist's limbs. Distance cyclists are subjected to mechanical vibrations, which, while less intense than those to which off-road cyclists are exposed, can over time cause portions of their bodies to ache and become numb.
One part of the bicycle through which vibrations are transferred to the cyclist is the handlebars. In most bicycles, vertical motion caused by the front wheel traveling over bumps or other uneven surfaces is only marginally attenuated by compression of the front tire. As a result, the motion is transferred through the front wheel fork assembly, through the stem of the assembly, through the handlebars attached to the stem, and from there into the hands and arms of the cyclist where it is absorbed by his/her joints. At the least, repeated exposure to this rapid up and down motion can cause parts of one's body to go numb and serves only to detract from the pleasure of cycling. At the worst, this repeated shock can induce individual pain or injury to the point where some individuals simply find it necessary to forgo bicycling.
There have been some attempts to provide shock-absorbing handlebars to minimize vibration transferred from bicycle to cyclist. These assemblies have typically comprised providing a linkage that allows the handlebars to pivot in an arc relative to a point on a line running through the front fork assembly stem. These assemblies have often been provided with some type of compressible member to damp the pivoting motion. A disadvantage of these assemblies is that they expose the cyclist's hands and arms to a downward and rearward pivoting motion that produces a whole new set of strains on the cyclist's body. Also, since almost all cyclists ride with the back portions of their hands facing forward, this inward and downward motion can be uncomfortable for the cyclist. Furthermore, because of these adverse effects of the pivoting motion, many of the assemblies are designed so that they allow the handlebars to have only a limited degree of movement. Consequently, the amount of vibration these assemblies are able to absorb is limited. Moreover, the design of many of these assemblies has made them unsuitable for use with triathlon handlebars and other nonstandard handlebars, which are favored by a growing number of cyclists. These assemblies also do not allow for adjustment of their static rise angle. Thus, the present assemblies have proved to be of little value for reducing the vibrations to which a great number of cyclists are exposed.